Spraybar device



Feb. 12, 1957 R w, THORNBURG 2,781,229

SPRAYBAR DEVICE Filed Aug. 18, 1954 point of durability of the treatedroad surface.

United States Patent() SPRAYBAR DEVICE Robert W. Thornburg, Minneapolis,Minn., assignor to Rosco Manufacturing Company, Minneapolis, Minn., acorporation of Minnesota f Application August 1s, 1954, serial No.450,718

z claims. (ci. zits- 34) material so as to prevent gapping between thesprayed,

pathways or to prevent overlap of a spray during operation. Although thebest average height is sought to be attained, it is not generallyrecognized that variation from the predetermined height of the nozzlesfrom the road surface by as little as a quarter of an inch willseriously effect the quality of the treated road. I have found thatstreaking is both costly and improper from the stand- The streakedapplication of bituminous material ycauses a line of over-richapplication adjacent a line of insuiiicient treatment. Even where anoverall excess of material is applied, the unevenness of suchapplication will cause trouble in the long range durability of thesurfaced road.

This invention attempts to correct such uneven and streaked applicationof road surfacing material by approaching the problem in a direct andsimple manner. Apparently designers of prior art spraybars were led awayfrom developing an unconventional type of support or mounting for thespraybar since there is no convenient way other than suspension from thetank truck frame in which t support a conventional spraybar.Furthermore, the rear wheels of the tank truck generally define theplane of surface over which the bituminous application is to be made,and hence the truck tires themselves have been utilized as the means forproperly spacing the spraybar and spraybar nozzles from the roadsurface.

Unfortunately, such spraybar mounting does not fully meet therequirements for maintaining exact spacing to prevent the abovementioned streaking of material, because the weight of the pay load`carried by the tank truck varies considerably during the application ofthe surfacing material. When the truck is first loaded, the weight ofthe tank on the truck frame and springs is so great as to cause theentire frame to assume a lower position and thereby bring the spraybarnozzles closer to the road surface. The result of operations with afully loaded tank truck of conventional design is the concentration ofsprayed bituminous material in a band or ribbon immediately beneath eachof the nozzles. A parallel band of insuiiiciently treated road surfacewill be formed in between each of the nozzles. As the applicationproceeds and the tank truck becomes partially emptied, the properspacing is acquired and good even application will be accomplished. Now,however, as the tank truck nears depletion, the pay load will beconsiderably lighter and the frame will ride at a higherl level on thertruck sup- 2,781,229 Patented Feb. 12, 1957 ICC porting springs. Inthis latter condition, the overlap of the spray width will be such as toproduce a greater concentration of bituminous material in bandsintermediate the spray nozzles and to cause an inadequate spraying inbands immediately beneath each of the spray nozzles. The production ofsuch streaks has been deemed a necessary evil, but I have found thatsuch is not the case. It is possible to obtain perfect adjustment and toobtain the best possible surfacing at all times so as to project thedurability of the bituminous road far beyond the life of theaverageyroad treated by conventional methods.

It is therefore an important object of this invention to provide a newand improved spraybar device which will deliver a consistent and evencoating of bituminous material to the surface of a road in an efficientand economical manner.

It is another object of the invention to provide a spraybar which willmaintain consistent height from the road bed regardless of the weight ofthe material in the truck tank and'regardless of the equilibriumposition of the truck frame.

It is a further object of the invention to provide a spraybar of theclass described in which ground contacting members maintain theprescribed height of the nozzle tips from the surface of the road whilepermitting turning of the equipment and travel over a changing grade.

It is a still further object of the invention to provide a simplecombination spraybar and iXed height support which is so yconstructed asto be non-fouling yet will permit free movement of the spraybar properduring operation of the device.

These and other objects and advantages of the invention will more fullyappear from the following description made in connection with theaccompanying drawings, wherein like reference characters refer to thesame or similar parts throughout the several views, and in which: I

Fig. 1 is a rear View of the spraybar assembly with the side wings ofthe spraybar in raised condition and the support in ground-contactingposition; and

Fig. Z is a vertical cross-sectional detail of my spraybar deviceshowing the particular cooperative attachment of a wheel element to thetubular spraybar, the section being taken on the line 2--2 of Fig. 1.

With continued reference to the drawings, my invention contemplatesattachment to and communication with a conventional bituminous tanktruck indicated generally at 10 in Fig. 2, the illustration showing therear portions of the tank 11, the tank truck rear wheels 12 and aconventional truck frame 13 which supports the entire weight of the tankin resilient support with respect to the wheel members 12.

A conventional mounting structure is indicated generally at 14 and issecured to a rearwardly extending portion of the truck frame 13 as shownin Figs. l and 2. The mounting structure .in addition has a pair ofdepending cables 1S and 16 which are supported on spools 17 and 18, bothof which are secured to a shaft 19 which is journaled across thesupporting structure 14 and geared to a manual crank 20 for raising andlowering cables 1S and 16. The lower portion of the supporting structurecomprises a horizontal member 21 which is suspended by means of brackets22 and 23 from the respective cables 15 and 16 as shown. The horizontalmember 21 has a pivot block 24 to which is secured a handle 25 inpivotal relation at 26 and a lower end 27 of which is pivoted to a brace28 at the pivot point 29. Pivot arm 30 coextends between pivot 29 andthe pivot support 31 which in turn is secured to link rod 32 as shown inFig. l. The brace 28 has asimilar pivotal connection at 33 to arm 34which is pivotally mounted at 35 on pivot block 36 secured to the member21 and having a lower extension 37 pivotally connected at 38 to a link39 which is turn pivotally connects with a bracket 40 secured in turn toanother link rod 32. Rigid depending me-mbers 41 and 42 in the attachingor mounting structure for the spraybar device permits the raising andlowering the spraybar 32 while maintaining. the spraybar tube ingenerally horizontal relation with the road surface 43 to be sprayed andwhile maintaining the spraybar tube in firm horizontal spaced relationwith the tank truck frame 13.

A plurality of spray nozzles 44 are disposed in fluid connection withthe spraybar tube sections 45 and are disposed in depending relationtherewith for delivery of sprayed bands of bituminous material to theroad bed 43 in a continuous and even manner, as shown in Fig. l.

Outside spraybar tube connections 46 are equipped with similar nozzlese4 at each side of the device and have folding linkage members 47 whichconnect with a linking rod i at. each side of the. device for yoperatingthe respective nozzles 44 on the spraybar tube wings 46. As isconventional, the spraybar tubes constituting the outer wing extensionsmay be raised to theV position shown in Fig. l where the nozzles willremain inactive and the horizontal spraybar tubes may be alone operatedto cover a narrower swath when desired.

A liexible tubular fluid connection 49 interconnects with an outlet 56Bleading from the tank il and communicates with the lluid connection 51for supplying bituminous material to both sides of the spraybar tubesections. The spraybar #l5 is shown in cross-section in Fig. 2 andconstitutes a rigid elongated member extending transversely of the tanktruck at the rear thereof in suspended relation as previously describedso that it may move upwardly and downwardly with respect to the tanktruck 1l) but may not move forwardly or backwardly except in unison withthe travel of the truck.

The spraybar tube 4S has secured thereto in spaced relation, a. pair ofroller supports indicated generally at 52 in Fig. 2. The roller supportsin turn comprise a pair of spaced bearing brackets 53 which are weldedor otherwise rigidly secured to the spraybar i5 at each side and extendupwardly and forwardly thereof to terminate in a bearing 5d having agenerally Vertical axis. Mounted within each of said bearings 54 is atruck mount 55 having a vertical stub shaft S6 secured by fastener 57 tothe upper end of bearing 54 and having a bearing plate 5S in rotatablecontact with the underside of bearing 54 for easy rotation therewith.The truck mounts each have a pair of forked depending members 59 whichterminate at their lower ends in a wheel shaft 6l) extending thereacrossand upon which a rubber tired wheel 6l is rotatably mounted` Means suchas cotter pins 62 may be secured through the shafts 6G for maintainingthe wheels 6l. in rotative position within the truck mounts 59 as shownin Fig. 2. l't will be observed that the bearing brackets 53 are angledupwardly and forwardly/while the forked lower portion of the truckmounting 59 is angled downwardly and rearwardly. The elfect of thisparticular mount is such as to permit a wheel 61 of ple diameter tosupport the spraybar tube 45 in predetermined spaced height withrelation to the road surface A33 and yet lying in clearance with allparts of the spraybar device including the spraybar tube, the spraynozzles 4d and the projected path of bituminous material emanatingtherefrom, as well as the other portions of the mounting structure. Allthis has been accomplished while maintaining a proper diameter of therubber tired wheel 6l to adequately support the spraybar and associatedparts.

ln the use and operation of my device, the rubber tired wheels 6l areinflated to a predetermined pressure so as to exactly maintain theproper spacing from the tips of the spray nozzles 44 to the road surface43 and this space should be maintained at all times. the particularapparatus first used for the principle disclosed herein, l have selecteda distance of 8% inches,

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taking into consideration the design of the spray nozzles 44 to effectan evenly applied coating of bituminous material without gaps or withoutoverlap. As the tank truck proceeds during the bituminous coatingoperation, the curvature of the road may be followed without varying thepredetermined height of the nozzles, the rubber tired Wheels 61 merelyturning on the vertical shaft 56 in the aforementioned clearance toaccommodate the change in direction. lf, on the other hand, the tanktruck proceeds over hills and valleys in the road to be surfaced, thenozzles 44 will not ride upwardly and downwardly with respect to theroad surface 43, but rather will be maintained at the close tolerance ofheight previously noted during the operation. The spraybar tube will,however, adjust itself vertically with respect to the truck frame 1l andwill be permitted to ride upwardly and downwardly with respect to thebrace members 4i and 42 which are rigidly secured to the truck frame i3.The cables 15 and lo are of course, relaxed sufficiently to permitdownward movement of the spraybar as the truck passes over the crest ofa hill, it being borne in mind that the wheeled supports always maintainthe exact height of the spray nozzles from the road surface 43.

It may thus be seen that l have devised a simple additional mountingstructure in combination with a conventional spraybar tube which willmaintain the nozzle members at exactly the proper height at all times toapply an even and durable coating of bituminous material to a roadsurface, the mounting having unique cooperation with the remainder ofthe spraybar device for adequately supporting the structure and havingthe proper dimensions for accomplishing the purpose described, yet beingnon-clogging in character and lying in complete clearance with all theother portions of the device as well as the projected path of thesprayed bituminous material.

It will, of course, be understood that various changes may be made inthe form, details, arrangement and proportion of the various partswithout departing from the scope of my invention What is claimed is:

l. A spraybar assembly `for applying road surfacing huid materialcomprising, an elongated tubular member horizontally disposed in saidassembly and having depending spray` nozzles communicating at spacedintervals therewith and liexible lluid connection for supplying roadsurfacing fluid to the tubular member, a mountn ling structureattachable rigidly to the rear end of a bitul closely adjacent theprojected path of sprayed material as well as in clearance with thetubular member and mountin g structure.

2. A spraybar assembly for applying road surfacing lluid materialcomprising, an elongated tubular member horizontally disposed in saidassembly and having depending spray nozzles communicating at spacedintervals therewith and flexible fluid connection for supplying the roadsurfacing fluid to the tubular member, a mounting structure rigidlyattachable to the rear end of a conventional bituminous tank truck andmaintaining the tubular member transversely of the direction of travel,said mounting structure having vertical guide means for the tubularmember and a pair of spaced roller supports mounted to the tubularmember at a lower position and slightly forwardly thereof with respectto the direction of travel of the tank truck during operation, wherebythe tubular member will at all times be maintained at a uniformpredetermined height from the road surface irrespective of 991,043variations in the height of the rear end o-f the tank truck 2,031,262because of changes in the Weight of fluid in the tank. 2,663,973

References Cited in the tile of this patent 5 UNITED STATES PATENTS4911882 980,002 Price Dec. 27, 1910 6 Ward May 2, 1911 Hill Feb. 18,1936 White Dec. 29, 1953 FOREIGN PATENTS Germany Feb. 17, 1930

